Steam hammer



March 16, 1965 H. TERHUNE STEAM HAMMER Filed 061'.. 3, 1962 INVENToR. Howard Terlvune ATTORNEYS l l] \1L Il mqlwgatw United States Patent C) 3,173,285 EAM Howard Terhune, 2640 Ridgewood Ave., Alliance, Ohio Filed Oct. 3, 1962, Ser. No. 228,062 4 Claims. (Cl. 72-342) The invention relates to steam hammers and more particularly to a steam hammer having a floating piston rod and automatic stroke mechanism.

It is an object of the invention to provide a steam hammer in which the lower end of the piston rod is slidably located within the upper portion of the ram in which an oil cushion is provided to decelerate the rod after ram impact.

Another object of the invention is to provide such a construction in which the piston rod is hollow so that steam may be circulated therethrough for cooling the piston rod.

A further object of the invention is to provide a steam hammer of the character referred to having valve linkage providing an automatic stroke of the piston rod and ram.

Another object of the invention is to provide such a ysteam hammer in which the control valve is provided with a bleeder vent for normally holding the ram in raised position.

A further object of the invention is to provide a steam hammer of this character in which a novel spring lock is provided in the valve linkage.

The above and `other objects, apparent from the drawing and following description, may be attained, the above described difiiculties overcome and the advantages and results obtained, by the apparatus, construction, arrangements and combinations, sub-combinations and parts which comprise the present invention, a preferred embodiment of which, illustrative of the best mode in which applicant has contemplated applying the principle, being set forth in detail in the following description and illustrated in the accompanying drawing, in which;

FIG. 1 is a front elevation of a steam hammer embodying the invention, arts being broken away for the purpose of illustration;

FG. 2 is an enlarged fragmentary sectional View of portions of the ram and piston rod; taken on line 2 2, PEG. l.;

FIG. 3 is an enlarged fragmentary sectional view of the control valve, showing the bleeder vent therein;

FIG. 4 is an enlarged sectional elevation of the spring lock in the Valve linkage; and

FIG. 5 is a plan section on the line 5 5, FIG. 1.

The steam hammer construction illustrated in the drawing comprises a base 1, having fabricated piers 2 and 3 extending upwardly therefrom and supporting the superstructure indicated generally at 4.

The anvil cap 5 is mounted upon the base 1 and supports the lower or stationary die block 6. Guideways 7 and d are provided upon the opposed sides of the piers 2 and 3 respectively, the ram 9 being vertically slidable thereon. The upper or movable die block 10 is carried by the ram for cooperation with the stationary lower die block 6.

In the superstructure 4 is located the vertical cylinder indicated generally at 11, the control valve indicated generally at 12, and the throttle valve indicated generally at 13. The steam cylinder 11 is shown as provided with a liner 14, and head 1S connected by bolts 16 to the upper end of the cylinder, through the annular franges 17 and 18 upon the cylinder and head respectively.

A safety cover 19 is located in the upper end portion of the cylinder 11, spaced from the head thereof, and a steam intake 241 is provided in the cylinder in the space between the safety cover 19 and the cylinder head 15.

The piston 21 is slidably mounted within the cylinder,

3,173,285 Patented Mar. 16, 1965 and the upper end of the hollow piston rod 22 is attached thereto as by screw threads 23. A central bore 24 in the piston communicates with the upper end of the bore 25 in the piston rod. The bore 25 terminates at a point near the lower end of the piston rod 22, as shown at 26 in FIG. 2.

As best shown in FIG. 2, the ram 9 is suspended upon the lower end of the piston rod 22 in such manner as to provide a hydraulic cushion. For this purpose the lower end portion of the rod 22 is vertically slidable through a gland 27 located in the upper end of the cavity 28 in the. ram 9.

This gland includes the annular member 29 screwthreaded as at 30 into the ram 9. The lower end of the rod 22 is tapered as at 31, and the collar 32, with tapered bore 33, is wedged thereon by means of the nut 34 screwed upon the threaded lower end 35 of the rod.

Restricted passages 36 in the collar 32 provide communication between the cavity 28 and the annular recess 37 in the lower end of the annular member 29, when the parts are in the full line position shown in FIG. 2. With the piston rod in the broken line position shown in said ligure, the passages 36 provide communication between the lower and upper portions of the cavity 2S below and above the collar 32.

The cavity 28 is adapted to be filled with oil which may be placed therein through the filling opening 38, adapted to be closed by screw plug 39.

A gland dll is located in the superstructure 4, at the bottom of the cylinder 11, for permitting reciprocation of the piston rod 22 therethrough while maintaining the cylinder steam-tight.

The throttle valve, indicated generally at 13, comprises a hollow cylinder 41 rotatable upon a horizontal axis and provided with a plurality of radial ports 42. The rotary cylindrical valve 41 communicates with the steam inlet passage 43 through the ports 44 and with the annular chamber 45 surrounding the control valve indicated generally at 12, through the ports 46.

A lever 47 upon the rotatable cylindrical valve 41 is connected by rod 4S with the throttle valve control device 49, which is manually operated to control communication between the steam inlet 43 and the steam chamber 45 of the control valve 12.

This control valve comprises the cylindrical valve casing 511 and the valve 51 vertically slidably mounted therein. This valve is in the form of a hollow cylinder having enlarged upper and lower ends 52 and 53 respectively, which slidably engage the inner surface of the valve casing 56, and the central body portion 54 of smaller diameter.

A rod 55 is connected to the upper end of the sliding valve member 51 and is slidably located through a gland 56 at the top of the cylinder 50, the upper end of the rod being conected by link 57 to a rocker arm 58 connected to rocker shaft 59 journalled in the bearing portion 69 iixed upon the cylinder 11.

A rocker arm 61, fixed upon the rocker shaft 59, is pivotally connected at 62 to the upper end of a link 63, the lower end of said link being pivotally connected, as at 64, to one arm 65 of a bell crank which is pivoted at 66 upon one end of the lever 67.

The other arm 68 of the bell crank is provided with a pin or roller 69 engaged in the elongated slot 70 formed in the upper end of the cam rodV 71, which is pivoted at 72 upon the pier 3.

A cam follower 73 upon the rod 71 is provided with rounded surface to engage the cam surface 74 at one side of the ram 9, said cam surface terminating at its upper end in the inwardly and upwardly inclined portion 75, and at its lower end in the inwardly and downwardly inclined portion 76.

Below the pivot point 72, a second cam follower 73' is fixed upon the cam rod 71 for engagement with the cam surface 74 of the ram.

The lever 67 is fulcrumed at 77 upon the pier 3 and the upper end of a link 78 is pivotally connected to the other end of the lever as indicated at 79. The lower end f the link 78 is pivotally connected as at 80 to a rocker arm S1 upon the rocker shaft 82.

A rocker arm 83 upon the shaft S2 is pivotally connected to the upper end of the link 84, the lower end of which is connected to the treadle 85.

A spring lock is provided upon the cam follower rod 71 as shown in detail in FG. 4. This lock comprises a lever 86 fixed to the rod 71 at its pivotal point, the outer end of the lever being pivoted as at 87 to the plunger 85. This plunger is slidably located within the longitudinal bore 89 of the tubular spring casing 9i) which is pivoted at 91 upon the pier 3.

A coil spring 92 is located in the bore 8% and interposed between the inner end thereof and the end of the plunger 88. Upper and lower stops 93 and 94 are formed upon the pier 3 for engaging the lever 86 and limiting the upper and lower movements thereof.

In the operation of the hammer, when the throttle valve 13 is opened, steam from the inlet 43 will pass through the ports 44 into the rotary cylinder 41 through the ports 42 and through the ports 46 to the annular passage 45 passing through the ports 98 to the interior of the cylindrical valve casing Sti.

As the treadle S5 is depressed, through the linkage 84., 82, 7S, 67, 65, 63, 61, 58, 57 and 55, the control valve 51 will be raised, uncovering the passage 99 so that live steam will be admitted to the cylinder 11 above the piston 21 and at the same time uncovering the exhaust passage 100 so that exhaust steam from the cylinder may pass into the exhaust passage 101.

The piston will thus be driven downward, and through the piston rod 22 the ram 9 will descend, the movable die block contacting the stationary die block 6 as in customary manner.

An oil cushion is provided at this point, by the downward movement of the rod 22 relative to the ram 9, to the broken line position shown in FIG. 2, as oil from the oil chamber 2S in the ram is squeezed up through the restricted passages 36 in the collar on the rod, and into the annular chamber 3, in the ram, and then into the space between the top of the collar 32 and the bottom of the annular member 29.

As the ram 9 descends, the cam surface 74 thereof will move out of contact with the upper cam follower 73 and will later contact the lower cam follower 73', swinging the cam follower rod 71 upon its pivot 72, and through the elongated slot 7i) thereon operating the bell crank 65-68 to swing clockwise upon its pivot 66, and through the link 63, rocker arm 61, rocker shaft 59, rocker arm 58 and links 57-55 moving the control valve 51 downward so as to admit steam through the passage 190 permitting the steam to drive the piston upward raising the ram.

This rocker valve gear increases the impact energy approximately 30% over the Bement Miles wiper valve gear now in common use, even with all other conditions the same.

As the ram is raised, the cam follower 73' will ride out of contact with the cam surface 74 on the ram and the cam follower 73 will engage said cam surface and through the elongated slot 70 of the cam rod 71, the bell crank 65-68 and the linkage above described, the control valve will be again moved to position to admit steam through the passage 99 to the top of the piston, again driving the ram downward.

By holding the treadle down, this operation will be continuously repeated automatically as long as desired. With each operation of the cam rod 71 the lever 36 will contact either the upper or lower stop 93 or 94 as the case may be, the spring 92 acting upon the plunger $8 hoiding the rod in this position until it is moved again by engagement of one of the cam followers thereon with the cam surface 74 on the ram.

For the purpose of holding the piston up when the hammer is not in use, a bleeder vent 192 is formed in the lower portion of the control yvalve 51, so that with the control valve in the position shown in FIGS. l and 3 and the throttle valve open, sufficient steam will pass through the bleeder vent 192, as indicated by the arrows in FIG. 2, to li'l the cylinder 11 below the piston 21 and thus hold the piston in raised position.

In the foregoing description, certain terms have been used for brevity, clearness and understanding, but no unnecessary limitations are to be implied therefrom beyond the requirements of the prior art, because such words are used for descriptive purposes herein and are intended to be broadly construed.

Moreover, the embodiments of the improved construction illustrated and described herein are by way of example, and the scope of the present invention is not limited to the exact details of construction.

Having now described the invention or discovery, the construction, the operation, and vuse of preferred embodiments thereof, and the advantageous new and useful results obtained thereby; the new and useful construction, and reasonable mechanical equivalents thereof obvious to those skilled in the art, are set forth in the appended claims.

I claim:

l. A steam hammer including a base, a lower die block thereon, piers extending upwardly from the base, a verti-l cally disposed cylinder supported on said piers, a piston in said cylinder, a piston rod depending from the piston, guideways upon said piers, a ram suspended upon said piston rod and slidable in the guideways, an upper die block carried by said ram, a control valve for controlling admission of steam to said cylinder above and below said piston, a cam surface on said ram, a cam rod pivoted upon one pier, cam followers upon said cam rod for com tact with said cam surface, a manually operable treadle, linkage operatively connected to said treadle and to said cam rod and to said control valve, said linkage including a lever pivoted upon one pier, link means operatively connecting one end of said lever to said treadle, a bell crank pivoted upon the other end of said lever, there being a slot in said cam rod, means on one end of the bell crank engaged in said slot and means operatively connecting the other end of the bell crank to the control lever.

2. A steam hammer including a base, a lower die block thereon, piers extending upwardly from the base, a verti cally disposed cylinder supported on said piers, a pistoni in said cylinder, a piston rod depending from the piston, guideways upon said piers, a ram suspended upon saidpiston rod and slidable in the guideways, an upper die block carried by said ram, a control valve for controlling` admission of steam to said cylinder above and below salti piston, a cam surface on said ram, a cam rod pivoted upon one pier, cam followers upon said cam rod for contact with said cam surface, a manually operabie treadle, linkage operatively connected to said treadle and to said cam rod and to said control valve, and means in said linkage for causing said piston to automatically reciprocate continuously while the treadle is depressed, and a spring lock comprising a lever fixed to said cam rod at the pivotal point thereof, a plunger pivoted at one end upon the end of said lever, a tubular member pivoted at one end upon one pier, said plunger being slidably located in the other end of said tubular member, a coil spring in said tubular member engaging the end of said plunger, and spaced stop means on said one pier above and below said lever.

3. A steam hammer including a base, a lower die block. thereon, piers extending upwardly from the base, a vertically disposed cylinder supported on said piers, a piston in said cylinder, a piston rod depending from the piston, guideways upon said piers, a ram suspended upon said piston rod and slidable in the guideways, an upper die block carried by said ram, a control valve for controlling` admission of steam to said cylinder above and below said piston, a cam surface on said ram, a cam rod pivoted upon one pier, cam followers upon said cam rod for contact with said cam surface, a manually operable treadle, linkage operatively connected to said treadle and to said cam rod and to said control valve, said linkage including a lever pivoted upon one pier, link means operatively connecting one end of said lever to said treadle, a bell crank pivoted upon the other end of said lever, there being a slot in said cam rod, means on one end of the bell crank engaged in said slot and means operatively connecting the other end of the bell crank to the control lever, and a spring lock comprising a lever fixed to said cam rod at the pivotal point thereof, a plunger pivoted at one end upon the end of said last-named lever, a tubular member pivoted at one end upon said one pier, said plunger being slidably located in the other end of said tubular member, a coil spring in said tubular member engaging the end of Said plunger, and spaced stop means on said one pier above and below said last-named lever.

4. A steam hammer including a lower die block, a vertically disposed cylinder supported above said die block, a piston in said cylinder, a piston rod depending from said piston, guideways above said die block, a ram slidably suspended upon the lower end of said piston rod and slidable in said guideways, there being an oil cushion in the ram to decelerate the rod after ram impact, there being a bore from the top of the piston to a point near the lower end of the piston rod, and means for alternately admitting live steam to each end of the cylinder and discharging exhaust steam from the other end thereof, whereby on each down stroke live steam is circulated through said bore to the lower end thereof, and on each upstroke exhaust steam is discharged from said bore for cooling said ram and the lower end of said piston rod.

References Cited by the Examiner UNITED STATES PATENTS 790,566 5/05 Eicher 78-43 1,199,807 10/'16 Miller 91-431 1,893,187 1/33 Urbanck 78-43 FOREIGN PATENTS 490,946 3/53 Canada.

996,596 12/51 France.

673,031 5/ 52 Great Britain.

138,466 l/60 Russia.

MICHAEL V. BRINDISI, Primary Examiner.

WILLIAM I. STEPHENSON, Examiner. 

1. A STEAM HAMMER INCLUDING A BASE, A LOWER DIE BLOCK THEREON, PIERS EXTENDING UPWARDLY FROM THE BASE, A VERTICALLY DISPOSED CYLINDER SUPPORTED ON SAID PIERS, A PISTON IN SAID CYLINDER, A PISTON ROD DEPENDING FROM THE PISTON, GUIDEWAYS UPON SAID PIERS, A RAM SUSPENDED UPON SAID PISTON ROD AND SLIDABLE IN THE GUIDEWAYS, AN UPPER DIE BLOCK CARRIED BY SAID RAM, A CONTROL VALVE FOR CONTROLLING ADMISSION OF STEAM TO SAID CYLINDER ABOVE AND BELOW SAID PISTON, A CAM SURFACE ON SAID RAM, A CAM ROD PIVOTED UPON ONE PIER, CAM FOLLOWERS UPON SAID CAM ROD FOR CONTACT WITH SAID CAM SURFACE, A MANUALLY OPERABLE TREADLE LINKAGE OPERATIVELY CONNECTED TO SAID TREADLE AND TO SAID CAM ROD AND TO SAID CONTROL VALVE, SAID LINKAGE INCLUDING A LEVER PIVOTED UPON ONE PIER, LINK MEANS OPERATIVELY CONNECTING ONE END OF SAID LEVER TO SAID TREADLE, A BELL CRANK PIVOTED UPON THE OTHER END OF SAID LEVER, THERE BEING A SLOT IN SAID CAM ROD, MEANS ON ONE END OF THE BELL CRANK ENGAGED IN SAID SLOT AND MEANS OPERATIVELY CONNECTING THE OTHER END OF THE BELL CRANK TO THE CONTROL LEVER. 